source: trunk/source/processes/hadronic/models/chiral_inv_phase_space/cross_sections/src/G4QProtonNuclearCrossSection.cc @ 1199

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27// The lust update: M.V. Kossov, CERN/ITEP(Moscow) 17-June-02
28// GEANT4 tag $Name: geant4-09-03-cand-01 $
29//
30//
31// G4 Physics class: G4QProtonNuclearCrossSection for gamma+A cross sections
32// Created: M.V. Kossov, CERN/ITEP(Moscow), 20-Dec-03
33// The last update: M.V. Kossov, CERN/ITEP (Moscow) 15-Feb-04
34// --------------------------------------------------------------------------------
35// ****************************************************************************************
36// ***** This HEADER is a property of the CHIPS hadronic package in Geant4 (M. Kosov) *****
37// *********** DO NOT MAKE ANY CHANGE without approval of Mikhail.Kossov@cern.ch **********
38// ****************************************************************************************
39// Short description: CHIPS cross-sections for proton-nuclear interactions
40// -----------------------------------------------------------------------
41//
42//#define debug
43//#define pdebug
44//#define debug3
45//#define debugn
46//#define debugs
47
48#include "G4QProtonNuclearCrossSection.hh"
49
50// Initialization of the
51G4double* G4QProtonNuclearCrossSection::lastLEN=0; // Pointer to the lastArray of LowEn CS
52G4double* G4QProtonNuclearCrossSection::lastHEN=0; // Pointer to the lastArray of HighEn CS
53G4int     G4QProtonNuclearCrossSection::lastN=0;   // The last N of calculated nucleus
54G4int     G4QProtonNuclearCrossSection::lastZ=0;   // The last Z of calculated nucleus
55G4double  G4QProtonNuclearCrossSection::lastP=0.;  // Last used in cross section Momentum
56G4double  G4QProtonNuclearCrossSection::lastTH=0.; // Last threshold momentum
57G4double  G4QProtonNuclearCrossSection::lastCS=0.; // Last value of the Cross Section
58G4int     G4QProtonNuclearCrossSection::lastI=0;   // The last position in the DAMDB
59std::vector<G4double*>* G4QProtonNuclearCrossSection::LEN = new std::vector<G4double*>;
60std::vector<G4double*>* G4QProtonNuclearCrossSection::HEN = new std::vector<G4double*>;
61
62// Returns Pointer to the G4VQCrossSection class
63G4VQCrossSection* G4QProtonNuclearCrossSection::GetPointer()
64{
65  static G4QProtonNuclearCrossSection theCrossSection; //**Static body of Cross Section**
66  return &theCrossSection;
67}
68
69G4QProtonNuclearCrossSection::~G4QProtonNuclearCrossSection()
70{
71  G4int lens=LEN->size();
72  for(G4int i=0; i<lens; ++i) delete[] (*LEN)[i];
73  delete LEN;
74  G4int hens=HEN->size();
75  for(G4int i=0; i<hens; ++i) delete[] (*HEN)[i];
76  delete HEN;
77}
78
79// The main member function giving the collision cross section (P is in IU, CS is in mb)
80// Make pMom in independent units ! (Now it is MeV)
81G4double G4QProtonNuclearCrossSection::GetCrossSection(G4bool fCS, G4double pMom,
82                                                       G4int tgZ, G4int tgN, G4int PDG)
83{
84  static G4double tolerance=0.001;     // Tolerance (0.1%) to consider as "the same mom"
85  static G4int j;                      // A#0f Z/N-records already tested in AMDB
86  static std::vector <G4int>    colN;  // Vector of N for calculated nuclei (isotops)
87  static std::vector <G4int>    colZ;  // Vector of Z for calculated nuclei (isotops)
88  static std::vector <G4double> colP;  // Vector of last momenta for the reaction
89  static std::vector <G4double> colTH; // Vector of energy thresholds for the reaction
90  static std::vector <G4double> colCS; // Vector of last cross sections for the reaction
91  // ***---*** End of the mandatory Static Definitions of the Associative Memory ***---***
92#ifdef pebug
93  G4cout<<"G4QPrCS::GetCS:>>> f="<<fCS<<", p="<<pMom<<", Z="<<tgZ<<"("<<lastZ<<") ,N="<<tgN
94        <<"("<<lastN<<"),PDG=2212, thresh="<<lastTH<<",Sz="<<colN.size()<<G4endl;
95#endif
96  if(PDG!=2212) G4cout<<"-Warning-G4QProtonCS::GetCS:***Not a proton***,PDG="<<PDG<<G4endl;
97  G4bool in=false;                     // By default the isotope must be found in the AMDB
98  if(tgN!=lastN || tgZ!=lastZ)         // The nucleus was not the last used isotope
99  {
100    in      = false;                   // By default the isotope haven't been found in AMDB
101    lastP   = 0.;                      // New momentum history (nothing to compare with)
102    lastN   = tgN;                     // The last N of the calculated nucleus
103    lastZ   = tgZ;                     // The last Z of the calculated nucleus
104    lastI   = colN.size();             // Size of the Associative Memory DB in the heap
105    j  = 0;                            // A#0f records found in DB for this projectile
106#ifdef debug
107    G4cout<<"G4QPrCS::GetCS: the amount of records in the AMDB lastI="<<lastI<<G4endl;
108#endif
109    if(lastI) for(G4int i=0; i<lastI; i++) // AMDB exists, try to find the (Z,N) isotope
110    {
111      if(colN[i]==tgN && colZ[i]==tgZ) // Try the record "i" in the AMDB
112      {
113        lastI=i;                       // Remember the index for future fast/last use
114        lastTH =colTH[i];              // The last THreshold (A-dependent)
115#ifdef debug
116        G4cout<<"G4QPrCS::GetCS:*Found* P="<<pMom<<",Threshold="<<lastTH<<",j="<<j<<G4endl;
117#endif
118        if(pMom<=lastTH)
119        {
120#ifdef debug
121          G4cout<<"G4QPCS::GetCS:Found,P="<<pMom<<" < Threshold="<<lastTH<<",CS=0"<<G4endl;
122#endif
123          return 0.;                   // Energy is below the Threshold value
124        }
125        lastP  =colP [i];              // Last Momentum  (A-dependent)
126        lastCS =colCS[i];              // Last CrossSect (A-dependent)
127        if(std::fabs(lastP-pMom)<tolerance*pMom)
128        //if(lastP==pMom)              // VI do not use tolerance
129        {
130#ifdef pdebug
131          G4cout<<"..G4QPrCS::GetCS:.DoNothing.P="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
132#endif
133          //CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // Update param's only
134          return lastCS*millibarn;     // Use theLastCS
135        }
136        in = true;                     // This is the case when the isotop is found in DB
137        // Momentum pMom is in IU ! @@ Units
138#ifdef debug
139        G4cout<<"G4QPrCS::G:UpdatDB P="<<pMom<<",f="<<fCS<<",lI="<<lastI<<",j="<<j<<G4endl;
140#endif
141        lastCS=CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // read & update
142#ifdef debug
143        G4cout<<"G4QPrCS::GetCrosSec: *****> New (inDB) Calculated CS="<<lastCS<<G4endl;
144#endif
145        if(lastCS<=0. && pMom>lastTH)  // Correct the threshold (@@ No intermediate Zeros)
146        {
147#ifdef debug
148          G4cout<<"G4QPrCS::GetCS: New P="<<pMom<<"(CS=0) > Threshold="<<lastTH<<G4endl;
149#endif
150          lastCS=0.;
151          lastTH=pMom;
152        }
153        break;                         // Go out of the LOOP
154      }
155#ifdef debug
156      G4cout<<"-->G4QPrCrossSec::GetCrosSec: pPDG=2212, j="<<j<<", N="<<colN[i]
157            <<",Z["<<i<<"]="<<colZ[i]<<G4endl;
158#endif
159      j++;                             // Increment a#0f records found in DB
160    }
161#ifdef debug
162    G4cout<<"-?-G4QPrCS::GetCS:RC Z="<<tgZ<<",N="<<tgN<<",in="<<in<<",j="<<j<<" ?"<<G4endl;
163#endif
164    if(!in)                            // This isotope has not been calculated previously
165    {
166#ifdef debug
167      G4cout<<"^^^G4QPrCS::GetCS:CalcNew P="<<pMom<<", f="<<fCS<<", lastI="<<lastI<<G4endl;
168#endif
169      //!!The slave functions must provide cross-sections in millibarns (mb) !! (not in IU)
170      lastCS=CalculateCrossSection(fCS,0,j,2212,lastZ,lastN,pMom); //calculate & create
171      //if(lastCS>0.)                   // It means that the AMBD was initialized
172      //{
173
174        lastTH = ThresholdEnergy(tgZ, tgN); // The Threshold Energy which is now the last
175#ifdef debug
176        G4cout<<"G4QPrCrossSection::GetCrossSect: NewThresh="<<lastTH<<",P="<<pMom<<G4endl;
177#endif
178        colN.push_back(tgN);
179        colZ.push_back(tgZ);
180        colP.push_back(pMom);
181        colTH.push_back(lastTH);
182        colCS.push_back(lastCS);
183#ifdef debug
184        G4cout<<"G4QPrCS::GetCrosSec:recCS="<<lastCS<<",lZ="<<lastN<<",lN="<<lastZ<<G4endl;
185#endif
186        //} // M.K. Presence of H1 with high threshold breaks the syncronization
187#ifdef pdebug
188      G4cout<<"G4QPrCS::GetCS:1st,P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
189#endif
190      return lastCS*millibarn;
191    } // End of creation of the new set of parameters
192    else
193    {
194#ifdef debug
195      G4cout<<"G4QPrCS::GetCS: Update lastI="<<lastI<<",j="<<j<<G4endl;
196#endif
197      colP[lastI]=pMom;
198      colCS[lastI]=lastCS;
199    }
200  } // End of parameters udate
201  else if(pMom<=lastTH)
202  {
203#ifdef debug
204    G4cout<<"G4QPrCS::GetCS: Current P="<<pMom<<" < Threshold="<<lastTH<<", CS=0"<<G4endl;
205#endif
206    return 0.;                         // Momentum is below the Threshold Value -> CS=0
207  }
208  else if(std::fabs(lastP-pMom)<tolerance*pMom)
209  //else if(lastP==pMom)               // VI do not use tolerance
210  {
211#ifdef pdebug
212    G4cout<<"..G4QPCS::GetCS:OldNZ&P="<<lastP<<"="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
213#endif
214    return lastCS*millibarn;           // Use theLastCS
215  }
216  else                                 // It is the last used -> use the current tables
217  {
218#ifdef debug
219    G4cout<<"-!-G4QPCS::GetCS:UseCur P="<<pMom<<",f="<<fCS<<",I="<<lastI<<",j="<<j<<G4endl;
220#endif
221    lastCS=CalculateCrossSection(fCS,1,j,2212,lastZ,lastN,pMom); // Only read and UpdateDB
222    lastP=pMom;
223  }
224#ifdef debug
225  G4cout<<"==>G4QPrCS::GetCroSec: P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
226#endif
227  return lastCS*millibarn;
228}
229
230// The main member function giving the gamma-A cross section (E in GeV, CS in mb)
231G4double G4QProtonNuclearCrossSection::CalculateCrossSection(G4bool, G4int F, G4int I,
232                                        G4int, G4int targZ, G4int targN, G4double Momentum)
233{
234  static const G4double THmin=27.;     // default minimum Momentum (MeV/c) Threshold
235  static const G4double THmiG=THmin*.001; // minimum Momentum (GeV/c) Threshold
236  static const G4double dP=10.;        // step for the LEN (Low ENergy) table MeV/c
237  static const G4double dPG=dP*.001;   // step for the LEN (Low ENergy) table GeV/c
238  static const G4int    nL=105;        // A#of LEN points in E (step 10 MeV/c)
239  static const G4double Pmin=THmin+(nL-1)*dP; // minP for the HighE part with safety
240  static const G4double Pmax=227000.;  // maxP for the HEN (High ENergy) part 227 GeV
241  static const G4int    nH=224;        // A#of HEN points in lnE
242  static const G4double milP=std::log(Pmin);// Low logarithm energy for the HEN part
243  static const G4double malP=std::log(Pmax);// High logarithm energy (each 2.75 percent)
244  static const G4double dlP=(malP-milP)/(nH-1); // Step in log energy in the HEN part
245  static const G4double milPG=std::log(.001*Pmin);// Low logarithmEnergy for HEN part GeV/c
246#ifdef debug
247  G4cout<<"G4QProtNCS::CalCS:N="<<targN<<",Z="<<targZ<<",P="<<Momentum<<">"<<THmin<<G4endl;
248#endif
249  G4double sigma=0.;
250  if(F&&I) sigma=0.;                   // @@ *!* Fake line *!* to use F & I !!!Temporary!!!
251  G4double A=targN+targZ;              // A of the target
252#ifdef debug
253  G4cout<<"G4QProtNucCS::CalCS: A="<<A<<",F="<<F<<",I="<<I<<",nL="<<nL<<",nH="<<nH<<G4endl;
254#endif
255  if(F<=0)                             // This isotope was not the last used isotop
256  {
257    if(F<0)                            // This isotope was found in DAMDB =======> RETRIEVE
258    {
259      G4int sync=LEN->size();
260      if(sync<=I) G4cout<<"*!*G4QProtonNuclCS::CalcCrossSect:Sync="<<sync<<"<="<<I<<G4endl;
261      lastLEN=(*LEN)[I];               // Pointer to prepared LowEnergy cross sections
262      lastHEN=(*HEN)[I];               // Pointer to prepared High Energy cross sections
263    }
264    else                               // This isotope wasn't calculated before => CREATE
265    {
266      lastLEN = new G4double[nL];      // Allocate memory for the new LEN cross sections
267      lastHEN = new G4double[nH];      // Allocate memory for the new HEN cross sections
268      // --- Instead of making a separate function ---
269      G4double P=THmiG;                // Table threshold in GeV/c
270      for(G4int m=0; m<nL; m++)
271      {
272        lastLEN[m] = CrossSectionLin(targZ, targN, P);
273        P+=dPG;
274      }
275      G4double lP=milPG;
276      for(G4int n=0; n<nH; n++)
277      {
278        lastHEN[n] = CrossSectionLog(targZ, targN, lP);
279        lP+=dlP;
280      }
281#ifdef debug
282      G4cout<<"-*->G4QPr0tNucCS::CalcCS:Tab for Z="<<targZ<<",N="<<targN<<",I="<<I<<G4endl;
283#endif
284      // --- End of possible separate function
285      // *** The synchronization check ***
286      G4int sync=LEN->size();
287      if(sync!=I)
288      {
289        G4cout<<"***G4QProtonNuclCS::CalcCrossSect: Sinc="<<sync<<"#"<<I<<", Z=" <<targZ
290              <<", N="<<targN<<", F="<<F<<G4endl;
291        //G4Exception("G4ProtonNuclearCS::CalculateCS:","39",FatalException,"overflow DB");
292      }
293      LEN->push_back(lastLEN);          // remember the Low Energy Table
294      HEN->push_back(lastHEN);          // remember the High Energy Table
295    } // End of creation of the new set of parameters
296  } // End of parameters udate
297  // ============================== NOW the Magic Formula =================================
298#ifdef debug
299  G4cout<<"G4QPrNCS::CalcCS:lTH="<<lastTH<<",Pmi="<<Pmin<<",dP="<<dP<<",dlP="<<dlP<<G4endl;
300#endif
301  if (Momentum<lastTH) return 0.;      // It must be already checked in the interface class
302  else if (Momentum<Pmin)              // High Energy region
303  {
304#ifdef debug
305    G4cout<<"G4QPrNCS::CalcCS:bLEN A="<<A<<", nL="<<nL<<",TH="<<THmin<<",dP="<<dP<<G4endl;
306#endif
307    if(A<=1.) sigma=0.;
308    else      sigma=EquLinearFit(Momentum,nL,THmin,dP,lastLEN);
309#ifdef debugn
310    if(sigma<0.)
311      G4cout<<"G4QPrNuCS::CalcCS:A="<<A<<",E="<<Momentum<<",T="<<THmin<<",dP="<<dP<<G4endl;
312#endif
313  }
314  else if (Momentum<Pmax)              // High Energy region
315  {
316    G4double lP=std::log(Momentum);
317#ifdef debug
318    G4cout<<"G4QProtNucCS::CalcCS: before HEN nH="<<nH<<",iE="<<milP<<",dlP="<<dlP<<G4endl;
319#endif
320    sigma=EquLinearFit(lP,nH,milP,dlP,lastHEN);
321  }
322  else                                 // UHE region (calculation, not frequent)
323  {
324    G4double P=0.001*Momentum;         // Approximation formula is for P in GeV/c
325    sigma=CrossSectionFormula(targZ, targN, P, std::log(P));
326  }
327#ifdef debug
328  G4cout<<"G4QProtonNuclearCrossSection::CalcCS: CS="<<sigma<<G4endl;
329#endif
330  if(sigma<0.) return 0.;
331  return sigma;
332}
333
334// Electromagnetic momentum-threshold (in MeV/c)
335G4double G4QProtonNuclearCrossSection::ThresholdMomentum(G4int tZ, G4int tN)
336{
337  static const G4double third=1./3.;
338  static const G4double pM = G4QPDGCode(2212).GetMass(); // Projectile mass in MeV
339  static const G4double tpM= pM+pM;       // Doubled projectile mass (MeV)
340  G4double tA=tZ+tN;
341  if(tZ<.99 || tN<0.) return 0.;
342  else if(tZ==1 && tN==0) return 800.;    // A threshold on the free proton
343  //G4double dE=1.263*tZ/(1.+std::pow(tA,third));
344  G4double dE=tZ/(1.+std::pow(tA,third)); // Safety for diffused edge of the nucleus (QE)
345  G4double tM=931.5*tA;
346  G4double T=dE+dE*(dE/2+pM)/tM;
347  return std::sqrt(T*(tpM+T));
348}
349
350// Calculation formula for proton-nuclear inelastic cross-section (mb) (P in GeV/c)
351G4double G4QProtonNuclearCrossSection::CrossSectionLin(G4int tZ, G4int tN, G4double P)
352{
353  G4double sigma=0.;
354  if(P<ThresholdMomentum(tZ,tN)*.001) return sigma;
355  G4double lP=std::log(P);
356  if(tZ==1&&!tN){if(P>.35) sigma=CrossSectionFormula(tZ,tN,P,lP);}// s(pp)=0 below 350Mev/c
357  else if(tZ<97 && tN<152)                // General solution
358  {
359    G4double pex=0.;
360    G4double pos=0.;
361    G4double wid=1.;
362    if(tZ==13 && tN==14)                  // Excited metastable states
363    {
364      pex=230.;
365      pos=.13;
366      wid=8.e-5;
367    }
368    else if(tZ<7)
369    {
370      if(tZ==6 && tN==6)
371      {
372        pex=320.;
373        pos=.14;
374        wid=7.e-6;
375      }
376      else if(tZ==5 && tN==6)
377      {
378        pex=270.;
379        pos=.17;
380        wid=.002;
381      }
382      else if(tZ==4 && tN==5)
383      {
384        pex=600.;
385        pos=.132;
386        wid=.005;
387      }
388      else if(tZ==3 && tN==4)
389      {
390        pex=280.;
391        pos=.19;
392        wid=.0025;
393      }
394      else if(tZ==3 && tN==3)
395      {
396        pex=370.;
397        pos=.171;
398        wid=.006;
399      }
400      else if(tZ==2 && tN==1)
401      {
402        pex=30.;
403        pos=.22;
404        wid=.0005;
405      }
406    }
407    sigma=CrossSectionFormula(tZ,tN,P,lP);
408    if(pex>0.)
409    {
410      G4double dp=P-pos;
411      sigma+=pex*std::exp(-dp*dp/wid);
412    }
413  }
414  else
415  {
416    G4cerr<<"-Warning-G4QProtonNuclearCroSect::CSLin:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
417    sigma=0.;
418  }
419  if(sigma<0.) return 0.;
420  return sigma; 
421}
422
423// Calculation formula for proton-nuclear inelastic cross-section (mb) log(P in GeV/c)
424G4double G4QProtonNuclearCrossSection::CrossSectionLog(G4int tZ, G4int tN, G4double lP)
425{
426  G4double P=std::exp(lP);
427  return CrossSectionFormula(tZ, tN, P, lP);
428}
429// Calculation formula for proton-nuclear inelastic cross-section (mb) log(P in GeV/c)
430G4double G4QProtonNuclearCrossSection::CrossSectionFormula(G4int tZ, G4int tN,
431                                                           G4double P, G4double lP)
432{
433  G4double sigma=0.;
434  if(tZ==1 && !tN)                        // pp interaction (from G4QuasiElasticRatios)
435  {
436    G4double p2=P*P;
437    G4double lp=lP-3.5;
438    G4double lp2=lp*lp;
439    G4double rp2=1./p2;
440    G4double El=(.0557*lp2+6.72+30./P)/(1.+.49*rp2/P);
441    G4double To=(.3*lp2+38.2)/(1.+.54*rp2*rp2);
442    sigma=To-El;
443  }
444  else if(tZ<97 && tN<152)                // General solution
445  {
446    //G4double lP=std::log(P);            // Already calculated
447    G4double d=lP-4.2;
448    G4double p2=P*P;
449    G4double p4=p2*p2;
450    G4double a=tN+tZ;                       // A of the target
451    G4double al=std::log(a);
452    G4double sa=std::sqrt(a);
453    G4double a2=a*a;
454    G4double a2s=a2*sa;
455    G4double a4=a2*a2;
456    G4double a8=a4*a4;
457    G4double a12=a8*a4;
458    G4double a16=a8*a8;
459    G4double c=(170.+3600./a2s)/(1.+65./a2s);
460    G4double dl=al-3.;
461    G4double dl2=dl*dl;
462    G4double r=.21+.62*dl2/(1.+.5*dl2);
463    G4double g=40.*std::exp(al*0.712)/(1.+12.2/a)/(1.+34./a2);
464    G4double e=318.+a4/(1.+.0015*a4/std::exp(al*0.09))/(1.+4.e-28*a12)+
465               8.e-18/(1./a16+1.3e-20)/(1.+1.e-21*a12);
466    G4double s=3.57+.009*a2/(1.+.0001*a2*a);
467    G4double h=(.01/a4+2.5e-6/a)*(1.+6.e-6*a2*a)/(1.+6.e7/a12/a2);
468    sigma=(c+d*d)/(1.+r/p4)+(g+e*std::exp(-s*P))/(1.+h/p4/p4);
469#ifdef pdebug
470    G4cout<<"G4QProtNucCS::CSForm: A="<<a<<",P="<<P<<",CS="<<sigma<<",c="<<c<<",g="<<g
471          <<",d="<<d<<",r="<<r<<",e="<<e<<",h="<<h<<G4endl;
472#endif
473  }
474  else
475  {
476    G4cerr<<"-Warning-G4QProtonNuclearCroSect::CSForm:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
477    sigma=0.;
478  }
479  if(sigma<0.) return 0.;
480  return sigma; 
481}
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